He apologised to the CBI officials and foreign delegates attending an international conference for briefly digressing from the topic "building a criminal justice system to deal with financial crimes".

Without taking the name of BJP or any other party, Chidambaram said, "There are several myths about the CBI ranging from the celebrated epithet 'caged bird' to the abusive nomenclature 'Congress Bureau of Investigation'. None of the descriptions is correct or even well-meaning."

Addressing a conference of CBI and state anti-corruption bureaux besides some international delegates, he said some of the myths are carefully fostered and propagated in order to serve an immediate or narrow self-interest.

"In a lighter vein, I may say that sometimes the CBI itself pretends to be a 'helpless victim' when it pleads for more powers and greater autonomy!," he said.

Giving political colour to his speech, the finance minister said, "Hardly anyone seems to notice the contradiction when the same person pleads in favour of 'more powers to CBI' and also rails against the alleged 'excesses of the CBI'.

"And hardly anyone pauses to ask how could the CBI do the bidding of a political party that has not been in government during 12 years out of the last 35 years," he said.

The statement from the finance minister comes a day after BJP accused UPA of misusing the CBI to shield itself from corruption and demanded more autonomy for the probe agency.

BJP's prime ministerial candidate Narendra Modi had claimed during a rally that CBI and terror group Indian Mujahideen had been let loose against him as the government could not tackle him politically.